ArticleOriginal scientific text
Title
On the isoperimetry of graphs with many ends
Authors 1
Affiliations
- Laboratoire de Mathématiques E. Picard, UMR CNRS 5580, Université Paul Sabatier, 118, route de Narbonne, F-31062 Toulouse Cedex, France
Abstract
Let X be a connected graph with uniformly bounded degree. We show that if there is a radius r such that, by removing from X any ball of radius r, we get at least three unbounded connected components, then X satisfies a strong isoperimetric inequality. In particular, the non-reduced -cohomology of X coincides with the reduced -cohomology of X and is of uncountable dimension. (Those facts are well known when X is the Cayley graph of a finitely generated group with infinitely many ends.)
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